Most modern portable cellular telephones have ports embedded within them that connect to some or all of the telephone's audio, data, power and RF lines. FIG. 1 illustrates two typical configurations for portable phones. Access to the audio lines of a portable enable these lines to be tapped in order to support a variety of accessory equipment such as modems or hands-free equipment. In all of these accessories, the audio transducers in the ear and mouth piece are disabled and replaced by audio inputs/outputs in the accessories. Thus in the case of a modem accessory, the transmit audio is the transmitted digital signal generated by the modem, and the received audio is routed to the modem for demodulation of the digital data stream. In the case of hands-free accessories, the audio functions of the ear and mouth piece are supplied by the external speaker and microphone, respectively of the hands-free accessory kit. Some portable phones also provide access to the portable RF output via a connector as well. In such a case, when the RF connector is not tapped, the portable sends/receives RF signals via its antenna. However, when the RF port is tapped, the RF path to the antenna is blocked and all the RF is routed via the connector. In FIG. 1a, a portable is illustrated that contains a port that supports both the audio and RF lines. In this case, the use of an accessory device is illustrated in which the connector bifurcates, routing the RF to an alternative antenna, and routing the audio lines to the accessory device. In FIG. 1b, a portable is illustrated in which the RF lines are not tapped. In this case, the portable's antenna continues to be used, and all the outputs from the connector are routed to the accessory device. In addition to RF and audio, many portable phones also provide power inputs on an external port to provide operating power to portable and battery charging as well.
The object of this invention is to provide an accessory device for portable phones that provides the simultaneous functionality of a hands-free accessory device and a data-in-voice modem. Thus, with the use of this invention, a portable phone can be used in a vehicle such that the driver can be engaged in a hands-free conversation at the same time that data (such as position information) is being sent over the same cellular channel.